Integrated Transcriptome Analysis Reveals Plant Hormones Jasmonic Acid and Salicylic Acid Coordinate Growth and Defense Responses upon Fungal Infection in Poplar

Abstract

Plants have evolved a sophisticated system to respond to various stresses. Fungal attack or infection is one of the most important biotic stresses for most plants. During the defense response to fungal infection, the plant hormones jasmonic acid (JA) and salicylic acid (SA) play critical roles. Here, gene expression data on JA/SA treatments and Melampsora larici-populina (MLP) infection were generated. Integrated transcriptome analyses of these data were performed, and 943 genes in total were identified as common responsive genes (CRG). Gene ontology (GO) term analysis revealed that the genes from CRG are generally involved in the processes of stress responses, metabolism, and growth and development. The further cluster analysis of the CRG identified a set of core genes that are involved in the JA/SA-mediated response to fungal defense with distinct gene expression profiles upon JA/SA treatment, which highlighted the different effects of these two hormones on plant fungal defenses. The modifications of several pathways relative to metabolism, biotic stress, and plant hormone signal pathways suggest the possible roles of JA/SA on the regulation of growth and defense responses. Co-expression modules (CMs) were also constructed using the poplar expression data on JA, SA, M. larici-populina, Septoria musiva, and Marssonina brunnea treatment or infection. A total of 23 CMs were constructed, and different CMs clearly exhibited distinct biological functions, which conformably regulated the concerted processes in response to fungal defense. Furthermore, the GO term analysis of different CMs confirmed the roles of JA and SA in regulating growth and defense responses, and their expression profiles suggested that the growth ability was reduced when poplar deployed defense responses. Several transcription factors (TFs) among the CRG in the co-expression network were proposed as hub genes in regulating these processes. According to this study, our data finely uncovered the possible roles of JA/SA in regulating the balance between growth and defense responses by integrating multiple hormone signaling pathways. We were also able to provide more knowledge on how the plant hormones JA/SA are involved in the regulation of the balance between growth and plant defense.

Biocontrol of Postharvest Fruit Fungal Diseases by Bacterial Antagonists: A Review

“…Numerous microbial antagonists of postharvest phytopathogens have been identified in laboratory and field studies and exploited commercially [12]. To date, the development of products based on beneficial microorganisms is relevant to reducing chemical contaminants in the food supply [80]. Microorganisms can be isolated from environments such as soil and sea, including some parts of plants [81].…”

Identification and evaluation of reliable reference genes for quantitative real-time PCR analysis in tea plants under differential biotic stresses

“…Validation of selected reference genes. JA and SA signaling pathways play key roles in plant defense against herbivorous insects 51,52 , and JA and SA responsive genes could be expressed upon herbivore attack or hormone stimuli 51,53 . A key transcription factor of JA signaling-CsMYC2, a key enzyme in the biosynthesis of JA-CsOPR3, two enzyme involved in the biosynthesis of SA-CsPAL and CsPALc were selected as target genes to validate the rationality of diurnal expression in different tissues, JA treatment and E. onukii infestation, T. aurantii infestation or E. obliqua regurgitant treatment individually.…”

The Role of Salicylic Acid in Plants Exposed to Heavy Metals

“…From the physiological point of view, it is known that SA plays a pivotal role in the regulation of plant growth, development, in defense from biotic and abiotic stress, and in plant immune responses [4,[19][20][21][22][23].…”

“…From that moment, an exponential increase of manuscripts focused on SA (acting alone or in concert with other plant hormones) as a plant growth regulator, signaling molecule, as well as plant elicitor protecting plants from biotic and abiotic stress, was observed [22,23,[26][27][28][29][30][31].…”